Chapter 4 Habitats
Dams can alter the timing and duration of flood events. Alteration of hydrology due to dam creation and the draining of wetlands change plant communities and also affect the availability of ephemeral wetlands for breeding amphibians. Building ditches and canals in floodplains dramatically alters hydrology and is often done to prepare a floodplain for agriculture, forestry, or development. Even in abandoned sites, ditches will continue to alter hydrology for many decades. Habitat loss from wetland drainage impacts all floodplain species, including furbearers, breeding amphibians, overwintering birds, and migrant species that use these areas as stopover sites. Fragmentation of forest stands has contributed to the loss of intact large riparian corridors, and the width of many riparian corridors has been greatly reduced. Breeding area-sensitive bottomland-hardwood birds have likely been impacted by the loss of intact woodland systems. High grading of stands has changed plant species diversity and stand vegetative structure. Forestry activities (e.g., logging) have reduced colonial waterbird and eagle nesting areas. Clearing of adjacent uplands can increase edge effects and limit the effective size of floodplain forest habitat. Water Quality. Sewer lines have been constructed along many floodplain corridors, especially in urbanized areas. These corridors fragment floodplain forests and allow conditions for invasion of exotic plant species. Poor water quality due to nutrient inputs, reduced dissolved oxygen (DO) levels, sedimentation, and chemical contamination (among others) can have a strong impact on amphibians, turtles, and other animals associated with floodplain forests that forage or breed in aquatic areas, in addition to the direct impacts on fully aquatic species. Sediment pollution is a major problem in the Piedmont and Coastal Plain. Beaver activity and the creation of beaver ponds in floodplain forest can have substantial impacts on trapping sediment and associated pollutants. Invasives. Increases in amounts of nonnative plants (e.g., Chinese Privet, Japanese Stiltgrass, Japanese Honeysuckle) and the overall loss of large canebrakes are partly due to the lack of infrequent fire and certain logging practices. Understory vegetative diversity has declined in many areas due to modified flooding regimes and increases in invasive nonnative plant species. The reduction in overall plant diversity is often extensive due to these invasive nonnative plants and may cause problems for native fauna, though the extent of wildlife impacts is largely unknown. 4.3.6.4 Climate Change Compared to Other Threats While climate change may not be the most severe threat, a combination of synergistic effects with other existing conditions could stress these systems to the point where several species are unable to persist. The effect of a changed climate is likely to vary widely among examples of this community type, depending on topographic sheltering, configuration of soil type and depth, elevation of groundwater, and the timing and duration of precipitation. Table 4.3.6-1 summarizes the comparison of climate change with other existing threats.
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2025 NC Wildlife Action Plan
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